U.S. patent number 5,779,386 [Application Number 08/698,370] was granted by the patent office on 1998-07-14 for apparatus and method for coupling support members.
This patent grant is currently assigned to Fisher-Price, Inc.. Invention is credited to Anthony E. Eichhorn.
United States Patent |
5,779,386 |
Eichhorn |
July 14, 1998 |
**Please see images for:
( Certificate of Correction ) ** |
Apparatus and method for coupling support members
Abstract
A joint for joining two tubes together that provides a
connection that is highly resistant to relative rotational movement
of the two tubes and that provides for connecting the tubes without
requiring tools. A tube with a swaged end of smaller diameter that
is to be joined to a second tube with a larger diameter contains an
interconnection member disposed within the swaged end of the tube.
The interconnection member is a button that is spring-biased to
extend through a hole in the swaged tube. The end of the swaged
tube also includes two slots, disposed on opposing sides of the
tube, that receive within them a rivet that extends transversely
through the larger diameter tube. As the swaged tube is inserted
into the larger diameter tube, the button in the swaged tube
springs into a corresponding hole in the larger diameter tube when
the holes in the swaged tube and the large diameter tube are in
alignment. Alignment of the button holes also aligns the slots of
the swaged tube with the transversely extending rivet in the larger
diameter tube such that the rivet is received within the slots of
the swaged tube. Any rotational force that is applied to either
tube will be resisted due to the rigid engagement of the rivet with
the sides of the slots that are disposed on opposing sides of the
swaged tube.
Inventors: |
Eichhorn; Anthony E. (East
Amherst, NY) |
Assignee: |
Fisher-Price, Inc. (Aurora,
NY)
|
Family
ID: |
24804958 |
Appl.
No.: |
08/698,370 |
Filed: |
August 15, 1996 |
Current U.S.
Class: |
403/329;
403/109.3; 403/328; 403/334; 403/377 |
Current CPC
Class: |
A47D
13/105 (20130101); F16B 7/0413 (20130101); Y10T
403/606 (20150115); Y10T 403/635 (20150115); Y10T
403/604 (20150115); Y10T 403/7077 (20150115); Y10T
403/32483 (20150115) |
Current International
Class: |
F16B
7/04 (20060101); B25G 003/18 () |
Field of
Search: |
;403/109,326,327,238,334,376,377,22 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Stodola; Daniel P.
Assistant Examiner: Lev; Bruce A.
Attorney, Agent or Firm: Morgan, Lewis & Bockius LLP
Talbot; C. Scott Richman; Howard R.
Claims
What is claimed is:
1. A joint for connecting two support members comprising:
a first swaged tubular support member having a first portion having
a first outside diameter, a third, end portion having a second
outside diameter smaller than said first outside diameter, a wall,
a longitudinal axis, an end, and a slot formed in said wall and
extending axially from said end, and a second portion extending
between said first and third portions, and tapering inwardly in
diameter from said first portion to said third portion;
a second tubular support member having an inner bore bounded by a
wall with an inside diameter larger than said second outside
diameter, a first aperture in said wall of said second support
member, and an elongate rotation restraint member disposed in said
bore and extending radially inwardly from said wall, said first
support member being slidingly receivable within said bore of said
second support member; and
a connecting member coupled to said first support member and
selectively extendable radially outwardly from said wall of said
first support member to an extended position and being engageable
with said aperture when in said extended position and when said
first support member is disposed in said second support member with
said rotation restraint member disposed in said slot,
engagement of said connecting member with said aperture preventing
axial withdrawal of said first support member from said second
member, and engagement of said rotation restraining member and said
slot preventing rotation of said first support member with respect
to said second support member.
2. The joint of claim 1 wherein said second portion tapers with a
linearly decreasing diameter as said second portion extends from
said first portion to said third portion.
3. The joint of claim 2 wherein said slot is formed in said third
portion.
4. The joint of claim 3 wherein said connecting member is a
v-shaped flat spring disposed within said second portion of said
first support member with a button disposed on a first end of said
spring and a second end of said spring supported against an
internal sidewall of said third portion of said first support
member, where said button is biased into an engagement position
through said first aperture to fixedly join said first and second
support members.
5. The joint of claim 1 wherein:
said first support member has an inner bore and a second aperture
extending from said bore through said wall of said third
portion;
said connecting member has a v-shaped flat spring disposed within
said inner bore with a first end engaged with a portion of said
inner bore radially opposite said second aperture and a button
disposed on the opposite end of said spring and disposed in said
second aperture, said button being biased by said spring into said
extended position.
6. The joint of claim 5 wherein said second aperture is axially
aligned with said slot.
7. A joint for connecting two support members comprising:
a first tubular support member having a wall with an outside
diameter, a longitudinal axis, an end, and a slot formed in said
wall and extending axially from said end;
a second tubular support member having an inner bore bounded by a
wall with an inside diameter larger than said outside diameter of
said first support member, a first aperture in said wall of said
second support member, and an elongate rotation restraint member
disposed in said bore and extending radially inwardly from said
wall, said first support member being slidingly receivable within
said bore of said second support member; and
a connecting member coupled to said first support member and
selectively extendable radially outwardly from said wall of said
first support member to an extended position and being engageable
with said aperture when in said extended position and when said
first support member is disposed in said second support member with
said rotation restraint member disposed in said slot,
engagement of said connecting member with said aperture preventing
axial withdrawal of said first support member from said second
member, and engagement of said rotation restraining member and said
slot preventing rotation of said first support member with respect
to said second support member,
wherein said first support member has an inner bore and a second
aperture extending from said bore through said wall;
said connecting member has a v-shaped flat spring disposed within
said inner bore with a first end engaged with a portion of said
inner bore radially opposite said second aperture and a button
disposed on the opposite end of said spring and disposed in said
second aperture, said button being biased by said spring into said
extended position.
8. The joint of claim 7 wherein said second aperture is axially
aligned with said slot.
9. A joint for connecting two support members comprising:
a first swaged tubular support member having a first portion, a
second portion and a third portion, where said first portion has a
first diameter, said third portion has a second diameter smaller
than said first diameter, and said second portion extends between
said first portion and said third portion and has a linearly
decreasing diameter as said second portion extends from said first
portion to said third portion;
said third portion having a first aperture in a sidewall and first
and second slots formed in the end of said third portion;
a second tubular support member of same diameter as said first
portion of said first support member, a second aperture in a
sidewall of said second support member, and a rotation restraint
member disposed internal to said second support member, wherein
said second support member internally receives said second and
third portions of said first support member; and
a connecting member removably positioned in said first and second
apertures to fixedly join said first and second support
members,
wherein said first and second slots in said third portion of said
first support member receive said rotation restraint member within
said slots when said first support member is inserted into said
second support member to restrict relative rotational movement of
said first support member and said second support member.
10. The joint of claim 9 wherein said connecting member is a
v-shaped flat spring disposed within said third portion of said
first support member with a button disposed on a first end of said
spring and a second end of said spring supported against the
internal sidewall of said third portion of said first support
member, where said button is biased into an engagement position
through said first and second apertures to fixedly join said first
and second support members.
11. A joint for connecting two support members comprising:
a first swaged cylindrical tube having a first portion, a second
portion and a third portion, where said first portion has a first
diameter, said third portion has a second diameter smaller than
said first diameter, and said second portion extends between said
first portion and said third portion and has a linearly decreasing
diameter as said second portion extends from said first portion to
said third portion;
said third portion having a first aperture in a sidewall and first
and second slots formed in the end of said third portion, where the
longitudinal axis of said first slot and said aperture are aligned,
and where said first and second slots are positioned 180.degree.
with respect to each other on opposing sidewalls of said third
portion;
a second cylindrical tube of same diameter as said first portion of
said first tube, having an elongated aperture larger than said
first aperture of said third portion, first and second circular
apertures positioned 180.degree. with respect to each other on
opposing sidewalls of said second tube, where the longitudinal axis
of said first aperture and said elongated aperture are aligned, and
a rivet disposed within said second tube and extending through said
first and second circular apertures, where said second and third
portions of said first tube are received within said second tube;
and
a v-shaped flat spring disposed within said third portion of said
first tube with a button disposed on a first end of said spring and
a second end of said spring is supported against the internal
sidewall of said third portion of said first tube, where said
button is biased into an engagement position through said first
aperture of said third portion and said elongated aperture of said
second tube to fixedly join said first and second tubes,
wherein said first and second slots formed in said third portion of
said first tube receive said rivet within said slots when said
second and third portions of said first tube are inserted into said
second tube to restrict relative rotational movement of said first
tube and said second tube.
Description
BACKGROUND OF THE INVENTION
The present invention relates to connectors for tubular structural
members.
Swings, other juvenile products such as playpens and strollers, and
other products that use metal tubes as structural elements are
commonly packaged with some or all of the tubes separated to
minimize the size of the package, and are assembled by the end
user. A common technique for joining two tubes end-to-end (along a
common longitudinal axis) is to swage the end of one of the tubes
(to reduce its diameter) and to sleeve the swaged end into the end
of the other tube. The tubes are prevented from separating
longitudinally by fixing a mechanical fastener to the mating ends
of both tubes, typically by one of two techniques. The first
technique involves drilling mating holes though one or both walls
of both tubes and placing a fastener such as a screw (if holes are
drilled through one wall) or a nut and bolt (if both walls are
drilled) through the holes. This technique produces a connection
that is generally highly resistant to relative axial and angular
movement of the tubes. However, it requires the end user to use
tools (screwdriver and/or wrenches) to fasten the tubes and makes
it relatively inconvenient to disassemble and reassemble the tubes.
The second technique again involves drilling mating holes through
one wall of the tubes, and placing a spring-loaded button inside
the swaged tube and protruding through the hole in the swaged tube.
When the other tube is sleeved onto the swaged tube and the hole in
that tube aligned with the button, the button springs into the
hole, fastening the tubes. Although this allows assembly without
tools and permits ready disassembly and reassembly (by pressing the
button radially inwardly into the swaged tube to clear the hole in
the other tube and pulling the tube free), the connection is not as
resistant to relative movement of the tubes as is the first
technique. This is because the holes must be formed slightly larger
than the outside diameter of the button to ensure that the button
can freely move through the holes. The slight relative axial
movement allowed by this connection technique is usually not
problematic. However, the relative angular movement is problematic
in situations where either or both tubes are connected to structure
that is substantially spaced from the tubes' common longitudinal
axis and that relies on angular registry of the tubes for proper
relative positioning. In such situations, a slight relative angular
movement at the joint can translate to substantial mispositioning
of the related structures. A joint that is easily assembled and
disassembled without tools yet which provides good resistance to
relative angular movement of the connected tubes would therefore be
desirable.
SUMMARY OF THE INVENTION
The drawbacks of the connection devices that are known are overcome
by the present invention which provides for ease in joining two
tubes together without requiring tools and which is highly
resistant to relative rotational movement of the two tubes. Through
the use of the present invention, structure supported by the
connected tubes is rigidly positioned and will not be subject to
mispositioning due to relative rotational movement of the
tubes.
In accordance with the present invention, a tube with a swaged end
of smaller diameter that is to be joined to a second tube with a
larger diameter contains an interconnection member disposed within
the swaged end of the tube for connecting the two tubes. The
interconnection member is a button that is spring-biased to extend
through a hole in the swaged tube. The end of the swaged tube also
includes two slots, disposed on opposing sides of the tube, that
receive within them the shaft of a rivet that extends transversely
through the larger diameter tube. As the swaged tube is inserted
into the larger diameter tube, the button in the swaged tube
springs into a corresponding hole in the larger diameter tube when
the holes in the swaged tube and the large diameter tube are in
alignment. The two tubes are thus coupled to prevent axial
separation. Since the button loosely engages the holes in the two
tubes, the tubes can rotate slightly relative to each other. To
reduce the amount of possible relative rotational movement of the
two tubes, the slots of the swaged tube receive the transversely
extending rivet in the larger diameter tube. Because the slots and
the rivet are sized for a tight fit, the possible relative
rotational movement is very small, since, any rotational force that
is applied to either tube will be resisted by the engagement of the
rivet with the sides of the slots that are disposed on opposing
sides of the swaged tube. Thus, relative rotational movement of the
two tubes is closely controlled.
The present invention provides for both connection of two tubes to
prevent axial disengagement and close control of relative
rotational movement of the two tubes. This stable positioning of
the two tubes is achieved by a relatively simple joint that
provides for easy assembly and disassembly of the tubes without
tools.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the joint as used in the context of
a leg of an infant swing.
FIG. 2 is an exploded perspective view of the joint of FIG. 1.
FIG. 3 is a side elevational view of the two support members of
FIG. 1.
FIG. 4 is a side elevational view of the joint of FIG. 1
FIG. 5 is a cross-sectional view of the joint of FIG. 1 taken along
line 5--5 of FIG. 4.
DETAILED DESCRIPTION
A joint embodying the principles of the present invention is
illustrated in FIG. 1 in the context of an infant swing. The swing
has angled, C-shaped legs that are subjected to torque about the
axis of the vertical portion of the leg. In the swing shown, the
legs are constructed with lower and upper tubular leg sections 100,
200 joined at a joint 10. Since the swing is shown only to
illustrate an application for the joint of the invention, in the
remainder of the application, the leg sections are referred to as
first and second support members 100, 200.
As shown in FIG. 2, joint 10 includes a first support member 100,
second support member 200, connecting member 170, and rivet
240.
As best seen in FIGS. 2 and 3, the first support member 100 is an
elongated, hollow bore, tube with a swaged joint end that has a
large diameter first portion 160, a transitional second portion 140
of decreasing diameter, and a smaller diameter third portion 110.
First portion 160 has an axially inner end 162 from which second
portion 140 extends axially and radially inwardly to axially outer
end 112 of third portion 110. (For definitional purposes herein,
axial inner and outer directions are defined as toward and away
from the joint ends of the support members, while radially inner
and outer directions are defined as toward and away from the
longitudinal axes of the support members individually or
collectively when joined on a common axis.) Third portion 110
extends from axially outer end 112 to an axially inner edge 111A of
support member 100.
The transition point between first portion 160 and second portion
140 defines shoulder 163. Second portion 140 and third portion 110,
together extending a distance X.sub.1 from shoulder 163 comprise
the swaged joint end 101 of support member 100.
Inner end 111 of third portion 110 includes radially opposed first
and second elongated rivet slots 144 and 147. Rivet slots 144, 147
are cut into the wall of third portion 110 from inner edge 111A and
extend longitudinally a distance X.sub.2 toward shoulder 163 to
their axially outer ends 144C, 147C, respectively, which have a
radius of curvature R.sub.1. Slots 144, 147 have a width W.sub.1
(twice R.sub.1). The slot outer ends 144C, 147C are positioned a
distance X.sub.4 from shoulder 163.
Inner end 111 of third portion 110 further includes circular button
aperture 142, which is a circular opening in the wall of third
portion 110 disposed axially outwardly of, and aligned axially
with, slot 144, and has a diameter D.sub.3. The axially outer end
of button aperture 142 is positioned a distance X.sub.3 from
shoulder 163.
First portion 160 has an outside diameter OD.sub.1, while third
portion 110 has an outside diameter OD.sub.2 and an inside diameter
ID.sub.1.
As seen in FIG. 2, connecting member 170 includes V-shaped flat
spring 174 and button 176 fixed at its radially inner end 178 to a
first end 174A of spring 174. Button 176 has a cylindrical body
portion 177 with diameter D.sub.4 and a radially outer end 179.
Connecting member 170 is disposed within third portion 110 of
support member 100 with second end 174B of spring 174 engaging the
interior wall of third portion 110 and with spring 174 biasing
outer end 179 of button 176 through button aperture 142. Diameter
D.sub.4 of cylindrical body portion 177 is slightly smaller than
diameter D.sub.3 of aperture 142 so that button 176 can extend
through aperture 142.
Second support member 200 is a cylindrical tube that has a joint
end 205 of uniform outside diameter OD.sub.3 and inside diameter
ID.sub.2 and terminates at an axially inner end 202. Outside
diameter OD.sub.3 of support member 200 and OD.sub.1 of first
portion 160 of support member 100 are substantially the same,
whereas inside diameter ID.sub.2 of inner end 202 is slightly
greater than outside diameter OD.sub.2 of third portion 110, so
that third portion 110 is slidably receivable in the inner bore of
inner end 202.
Joint end 205 includes a button receiving aperture 210, which is an
elongated hole that extends through the wall of joint end 205 and
has a width W.sub.2 that is approximately equal to diameter D3 of
button hole 142 (and thus slightly greater than the outside
diameter D.sub.4 of button 176), and a length L.sub.1 substantially
greater than width W.sub.2. The axially inner end 210C of aperture
210 is positioned a distance X.sub.3 from inner end 202 of joint
end 205.
Joint end 205 also contains first and second radially opposed rivet
receiving apertures 220, 221 axially aligned with aperture 210. A
rivet 240 is positioned in apertures 220, 221. Rivet 240 has an
elongated, cylindrical shaft 242 of diameter D.sub.5, that extends
through joint end 205, transverse to its longitudinal axis, and
into and through apertures 220, 221. Diameter D.sub.5 of shaft 242
is slightly smaller than width W.sub.1 of slots 144, 147 and the
inside diameter of apertures 220, 221 so that shaft 242 can be
securely received within slots 144, 147 and through apertures 220,
221. Each end 244, 246 of rivet 240 has a head 244A, 246A disposed
on it that is positioned external of, and in firm engagement with,
the outer surface of joint end 205 when rivet 240 is positioned
through member 200. Rivet 240 is positioned with its axially inner
edge spaced a distance X.sub.5 from inner end 202.
Aperture 210 of member 200 and slots 144, 147 of member 100 are
elongated so that sufficient margin is provided for positioning
button 176 within aperture 210 and rivet shaft 242 in slots 144,
147. This margin is required due to the swaging of member 100,
which results in a relatively high degree of axial dimensional
inaccuracy.
Joint 10 is shown in its engaged condition in FIGS. 4 and 5. When
the joint is engaged, swaged joint end 101 of support member 100 is
disposed inside joint end 205 of support member 200, and axially
inner end 202 of member 200 is positioned adjacent to shoulder 163
of member 100. Button 176 is disposed in button apertures 142 and
210, and rivet shaft 242 is disposed in slots 144, 147.
Joint ends 101 and 205 are joined in the engaged state by axially
aligning the joint ends so that the longitudinal centerlines of
button 176 and button aperture 210 are in alignment. When button
176 and button aperture 210 are in alignment, slots 144, 147 are
also properly oriented to receive rivet 240 within them. Button 176
is depressed into member 100 by applying a force to the button's
outer end 179 sufficient to overcome the biasing force of spring
174 and is maintained in the depressed position while third portion
110 of member 100, with smaller outside diameter OD.sub.2, is
inserted into joint end 205 of member 200, with larger inside
diameter ID.sub.2. Joint end 101 is inserted into joint end 205 a
distance X.sub.1 until end 202 of member 200 rests on shoulder
163.
When joint end 101 is inserted into joint end 205 in proper axial
alignment and to distance X.sub.1, button aperture 142 will align
with button receiving aperture 210, and spring 174 will urge button
176 radially outwardly to extend through aperture 210. Thus,
connecting member 170 connects joint end 101 within joint end 205
to prevent axial separation.
As joint end 101 is inserted into joint end 205, in addition to
connecting member 170 engaging joint end 205, first and second ends
244, 246 of rivet shaft 242 will enter and slide inside first and
second rivet slots 144, 147, respectively.
Since button aperture 210 is substantially larger than button body
portion 177, button 176 can move axially in button aperture 210.
Similarly, rivet shaft 242 can move axially in slots 144, 147.
Thus, joint ends 101 and 205 can move axially with respect to each
other. However, relative rotational movement of the two joint ends
is limited by the engagement of rivet shaft 242 with the sides of
slots 144, 147. If a rotational force is applied to member 100 as
shown in FIG. 4, left side 144B of slot 144, in fixed engagement
with rivet 240, and left side 147B of slot 147 (not shown) in fixed
engagement with rivet 240, will limit the relative rotational
movement of support members 100 and 200. If a force is applied in
the opposite direction, the right sides 144A, 147A of slots 144,
147, respectively, will interact with rivet 240 to prevent relative
rotational movement. Since shaft 242 diameter D.sub.5 and slot
width W.sub.1 can be adjusted to be very nearly the same (just
sufficiently different to permit rivet shaft 242 to slide through
slots 144,147), and their dimensions controlled to fairly close
tolerances, close control over relative rotation can be
achieved.
To disengage joint 10, button 176 is depressed radially inwardly
until it withdraws from button aperture 210, and joint end 101 is
then withdrawn axially from joint end 205.
In this manner, a joint is provided that allows for ease in
connecting two support members without requiring the use of tools
and that also prevents relative rotational movement of the support
members.
Several variations on the disclosed embodiment are contemplated.
Although rivet 240, disposed within second support member 200, and
slots 144, 147 in first support member 100, are positioned in the
same angular orientation as button apertures 142 and 210, they are
not required to be. Rivet 240 and slots 144, 147 can be positioned
in any angular orientation relative to apertures 142, 210.
Additionally, rivet 240 is not required to extend completely
through support member 200. Posts internal to support member 200,
disposed on opposing internal sidewalls and positioned to be
received within slots 144, 147, could also be utilized.
Connection member 170 is disclosed as spring 174 and button 176
disposed within support member 100, however, the connection member
can be any number of different structures and can be positioned
externally to the support members. For example, the connection
member can be a cylindrical pin that is mounted on the outside of
the larger diameter support member such that as the swaged member
is inserted into the larger diameter member, the pin is inserted
through corresponding holes in the two support members. The pin can
be biased into an engagement position or can be secured in position
through other structural means, namely, a cotter pin inserted
through the end of a pin that would extend entirely through both
support members.
Cylindrical tubes are disclosed as comprising support members 100
and 200 in the disclosed embodiment, however, the invention is not
limited to cylindrical tubes. The joint is equally capable of being
applied in the context where two rectangular, or other
geometrically shaped, support members are required to be joined and
securely positioned to prevent relative rotational movement.
* * * * *